MV Blog

DISPLAYING POSTS TAGGED: penguin awareness day (1)

Karen Rowe is a Research Associate at MV where she studies evolutionary ecology and behaviour in birds and mammals.

January 20th is an auspicious day for birding enthusiasts, marking Penguin Awareness Day. With 17 species currently recognised, members of the family Spheniscidae (pronounced sfen-IS-kuh-dee) are found only within the southern hemisphere. While most of us think of penguins as cold-adapted animals, surviving long treks over ice to breed and raise their young in the middle of winter, many species live further north, among the islands off of Antarctica, along the coasts of New Zealand and Australia, and one species is found on the Galapagos Islands (the aptly named Galapagos Penguin).

As a group, penguins possess an amazing array of adaptations, uniquely suited to their predominately marine existence. Unlike other birds, penguins have solid, rather than air-filled bones, to help them dive in the water. They have highly modified feathers that form a thick insulating layer that cover the body, rather than growing in the well-defined feather tract found in other birds. They also have unique eyes that allow them to see clearly both on land and in the sea. And while their short legs and feet make them seem awkward on land, many species actually travel tremendous distances over land and rocks to reach their breeding sites – some even traveling as far as three kilometres from water.

Extant species show a wide range of body sizes, from our own Little (or Fairy) Penguins, weighing 1.1 kg and standing 40 cm tall, to the largest species, the Emperor Penguin, at a whopping 30 kg and up to 115 cm tall.

But even the Emperor Penguin is dwarfed in size by some of the extinct fossil penguins, including a 15-million-year-old giant penguin (Anthropodyptes gilli) from Victoria that may have approached twice its size. Senior Curator of Vertebrate Palaeontology, Dr. Erich Fitzgerald studies fossil penguins here at Museum Victoria. "Victoria was home to a remarkable diversity of penguins over the last 20 million years," says Dr. Fitzgerald. "The tiny Little Penguin living in Australia today is an oddity on a geologic timescale. The fossil record tells us that most penguins that have lived in Australia were large to huge in size and that at any one time there were perhaps two or more species coexisting here." Currently, Dr. Fitzgerald and his student, Travis Park, are working on six-million-year-old fossil penguins found in Melbourne on the shores of Port Philip Bay that are thought to be the size of the living Gentoo and Emperor Penguins.

The upper wing bone (humerus) of living penguins compared with their fossil counterparts from Victoria. From left to right: the 18-million-year-old fossil Anthropodyptes gilli; the living emperor penguin Aptenodytes forsteri; the living fairy penguin Eudyptula minor; the living gentoo penguin Pygoscelis papua; and the 6-million-year-old fossil Pseudaptenodytes.
Credit: Photograph by Erich Fitzgerald
Image: Erich Fitzgerald Source: Museum Victoria

The unique ecology of penguins makes them particularly susceptible to a variety of human-induced threats. In particular, commercial fishing, often leading to death through by-catch or competition for prey items (which include fish, crustaceans, and cephalopods), directly impacts their survival. Penguins are also dependent on breeding grounds close to the shore and habitat loss is a major source of population declines. Smaller and fewer breeding grounds also promotes disease, as most species of penguins breed in large colonies.

Royal Penguin colony. This species is endemic to Macquarie Island and this is the largest Royal Penguin colony with over 180,000 breeding pairs. The fluffy young penguin in the front on the right is in moult.Image: Julie McInnesSource: Julie McInnes

Although little research has been done looking at the impact of climate change on penguins, their specialised lifestyle suggests that climate change could have dramatic impacts on their distribution and abundance. "Penguins are an ancient group of birds, with a history stretching back some 65 million years to the extinction of the dinosaurs," says Dr. Fitzgerald. "In southern Australia they have persisted through the last 20 million years of major climatic changes, but it is unknown how they will respond to the current human-exacerbated wave of environmental upheaval. It would be a terrible shame to see this ancient and superbly successful group of birds become threatened with extinction within our lifetime."